1. Field of the Invention
The present invention relates to a cooling system to be incorporated into an electronic apparatus, such as a television camera or an electronic still camera, having a device that generates heat, such as a solid-state imaging device.
2. Description of the Related Art
The applicant of the present patent application has previously proposed a cooling system for cooling the solid-state imaging device of a television camera in Japanese Patent Laid-open (Kokai) No. 3-58076. This previously proposed cooling system incorporated into a television camera has a heat transfer bag filled with a fluid having a high coefficient of thermal expansion and interposed between the solid-state imaging device and the cooling portion of a Peltier device, and a heat transfer pipe connecting the heat radiating portion of the Peltier device to the casing. The Peltier device cools the solid-state imaging device through the heat transfer bag, and heat generated by the Peltier device is transferred through the heat transfer pipe to the casing. The heat transfer bag is formed of a flexible material so that the heat transfer bag may not induce mechanical stress in the solid-state image sensor even if the Peltier device is not disposed in a correct position. However, this cooling system has the following disadvantages.
1. The fluid is likely to leak from the heat transfer bag.
2. The quantity of the fluid needs periodic inspection and replenishment because the fluid dissipates by evaporation.
3. The cooling system needs a pump and an associated mechanism additionally for circulating the fluid and these additional components increase the probability of malfunction.
4. Impurities contained in the fluid are likely to clog the fluid circulating circuit of the cooling system.
5. The performance of the heat transfer bag is subject to variation with changes in the atmospheric pressure and hence the cooling system cannot be used in a vacuum.